Thread a piece of floss through the hole and a needle, and then thread the needle through the front wire of your braces on your top teeth. Pull the needle all the way down until one side of the floss has fully come through the wire. Wrap the floss around your fingertips and pull it up in between your teeth. Pull the floss up and down in between your teeth, repeatedly. Thread another piece of floss through the hole and a needle. Then thread the needle through the front wire of your braces on your bottom teeth. Pull the needle all the way down until one side of the floss has fully come through the wire. Wrap the floss around your fingertips and pull it down in between your teeth. Pull the floss up and down in between your teeth repeatedly.